Sewing needle with easy threading filament loop

ABSTRACT

A sewing needle has a main body 10 and a closed loop 18 of a resilient filament material rigidly secured to the rear end of the main body and lying a single common plane with the lengthwise axis of the main body. In unstressed condition, the filament has an open diamond configuration allowing a sewing thread to be easily passed through it. As the needle is pulled through the fabric, the loop collapses under the forces imposes on its sides by the fabric and thereafter expands to reassume its unstressed configuration. The rigid securement of the loop to the main body of the needle ensures that the loop remains in a single common plane with the needle axis as it collapses upon passage through the fabric and as it expands to its unstressed configuration following such passage.

This is a continuation of co-pending application Ser. No. 297,194 filedon Oct. 12, 1988 now abandoned.

FIELD OF THE INVENTION

This invention relates to a sewing needle having a filament loop at itstrailing end so that the needle may be easily threaded.

BACKGROUND OF THE INVENTION

Because of the well-known difficulty of threading conventional manualsewing needles having narrow eyes formed at their trailing ends, a formof needle has been proposed incorporating a closed loop of a thinfilament secured to the rear end of the needle. Thread to be used withthe needle may be easily passed through the loop, which is substantiallylarger than the needle eye, and in use the loop is pulled through thefabric, behind the needle, carrying the thread through the fabric.

One form of such needle is disclosed in U.S. Pat. No. 1,293,660. Theloops disclosed in this patent are secured to the needles by passingthem through a conventional eye formed on the rear of the needle body.

Another form of looped needle, disclosed in U.S. Pat. No. 4,182,341, isintended primarily for surgical purposes. The needle body is formed witha truncated end having a central, dead-ended cavity opening at the end.The free ends of the filament forming the loop are secured within thiscavity and the loop projects from the rear of the cavity. Thisarrangement necessitates that the needle body have a thickness manytimes the diameter of the filament and can only be employed with verythick needles or with filaments that are so thin as to be practicallyinvisible.

The deficiencies of these previous designs for needles with followingloops have apparently prevented such needles from making any substantialmarket penetration against conventional needles, despite the obviousadvantages of the looped needle.

SUMMARY OF THE INVENTION

The present invention is accordingly directed toward a looped needle ofa unique design which preserves the advantages of looped needles whileovercoming the deficiencies of the prior art.

A preferred embodiment of the present invention utilizes a loop formedof a filament of thin spring steel wire, a plastic, or a similarmaterial which is readily deformable under slight pressures but ishighly resilient so as to immediately return to its normal configurationwhen the deforming forces are terminated and which will not assume anypermanent deformation under the range of forces normally encountered inuse. The filament is formed into a loop having a normal position,without the imposition of any external forces, lying in a single plane.The loop preferably has a generally diamond shape with two acute anglesat opposed ends and two obtuse angles intermediate these ends. The sidesof the loop adjacent the needle are preferably shorter than the loopsides remote from the needle so that the adjacent sides are moreresistant to closure than the remote sides and so that the angle at thefree, remote end of the loop is more acute than the angle at theadjacent end to facilitate the ability of the free end to grasp thethread. The loop is secured to the trailing end of the needle body atone of the acute angles so that the loop lies in a plane including theaxis of the needle and, in the absence of any deforming forces, the freeacute angle of the loop projects away from the needle body. The sides ofthe loop adjacent the needle are preferably shorter than the loop sidesremote from the needle so that the adjacent sides are more resistant toclosure than the remote sides and so that the angle at the free remoteend is more acute than the angle at the adjacent end to facilitate theability of the free end to grasp the thread.

In one embodiment of the invention, the trailing end of the needle bodyis preferably formed with a pair of concave depressions extendingaxially on diametrically opposed sides of the body. These depressionsmay be connected by a slit forming an eye in the manner of mostconventional loopless needles or alternatively, the trailing end of theneedle may be formed without an eye with just a pair of depressions ondiametrically opposed sides. In attaching the filament to the needle thefree ends of the filament lengths are laid in the two depressions andare secured to the needle body, preferably by crimping or swaging thesides over the filament ends so that the loop projects behind theneedle.

In another embodiment of the invention, the needle body and loop areformed from a single piece of material. This may be accomplished, forexample, by fabricating the needle body and loop, such as by injectionor compression molding, from a plastic having the desired properties ofhardness and resilience. This one-piece may then be coated or "flashed"with chrome or other metallic coating, if desired.

In yet another embodiment of the invention, an open loop of spring steelwire, shaped generally in the form of a diamond as described above, isprovided for attachment to conventional sewing needles. In its normalunstressed configuration, the open ends of the filament abut each other,forming one of the acute angles of the diamond. This attachment issecured to an existing conventional sewing needle by inserting the freeends of the filament into the needle eye and securing the abutting endsto each other and, preferably, to a portion of the inner surface of theneedle eye by spot welding or with a dry adhesive.

In all of the embodiments, the loop of the needle presents a wide targetfor attachment of the thread because of its normal diamond shapedconfiguration. The acute angle at the following end of the loop engagesthe thread to prevent the thread from slipping, allowing single threadsewing. Because of the rigid position of the loop relative to the needlebody, no difficulty is encountered in positioning the eye for threading.

The loop material may be distinctively colored, by anodizing or thelike, to increase the visibility of the loop and different size needlesmay be provided with loops of different colors to assist indistinguishing one size from another. Further, the loop may be formed ofa material which glows in response to receipt of light energy as toassist the user in clearly visually distinguishing the outline of theloop.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objectives, advantages and applications of the present inventionwill be made apparent by the following detailed description of preferredand alternative embodiments of the invention. The description makesreference to the accompanying drawings in which:

FIG. 1 is a plan view of a first embodiment of a looped needle formed inaccordance with the present invention;

FIG. 2 is a side view of the needle of FIG. 1;

FIG. 3 is a sectional view through the needle of FIG. 1 taken alonglines 3--3 of FIG. 2;

FIG. 4 is a plan view of an alternative embodiment of the inventionconstructed using a needle having a conventional eye;

FIG. 5 is a sectional view of the needle of FIG. 4 taken along lines5--5 of FIG. 4;

FIG. 6 is a perspective view of a single-piece embodiment of the needleof the present invention formed from injection molded plastic;

FIG. 7 is a plan view of an attachment clip formed in accordance withthe present invention; and

FIG. 8 is a partial view of the clip of FIG. 7 installed on aconventional sewing needle.

DETAILED DESCRIPTION OF THE INVENTION

In the embodiment of the invention illustrated in FIGS. 1-3, a stainlesssteel needle body 10, of appropriate diameter and length for handsewing, has a forward pointed end 12. The rear end of the needle istruncated at 14 and does not incorporate the eye found in conventionalneedles. A thread 16 to be used with the needle is attached to theneedle by passing it through a trailing filament loop, generallyindicated at 18.

The loop 18 is formed of a filament which is small in diameter incomparison to the needle body 10, preferably having a diameter nogreater than one-third of that of the needle body 10. The filament ispreferably metal wire such as spring steel. The wire is resilient andreadily deformable.

The wire filament 18 has a pair of free ends 20 which are secured to thetrailing end of the needle body 10 by virtue of being crimped, as by aswaging operation, within concave depressions 22 formed axially alongthe needle body for some distance from its trailing truncated end 14 andopening onto the truncated end. Alternatively, the filament ends couldbe welded, soldered or otherwise secured within the depressions 22. Theconcave depressions have a diameter preferably less than about 20% ofthe diameter of the needle body, so that they do not substantiallyweaken the needle body.

Loop 18 is formed with a generally diamond shape. The two free ends 20,in their unstressed condition, extend outwardly, away from one another,in the same plane, in sections 26, each of which preferably makes anacute angle with respect to the central axis of the needle. The sections26 terminate in obtuse angles at bends 28 which define the limits of thewidest separation of the loop. This separation between the bends 28 ispreferably several times the diameter of the needle body, providing awide target for easy threading.

The trailing end of the loop 18 is formed by a pair of filament sections30 which extend from the obtuse angle bends 28 to an acute angle rearbend 32 where they join one another. The sides 30 of the loop preferablyform a more acute angle relative to the central axis of the loop than dothe sides 26, so that the end of the loop to the rear of the bends 28 issubstantially longer than the section of the loop forward of the bends.This configuration assures that the relatively short loop sections 26will be relatively stiff compared to the relatively long loop sections30, maintaining the loop, which lies in a single plane with thelengthwise axis of the needle body 10, in an open configuration whenunstressed. It also increases the acuity of the rear angle bend 32 sothat bend readily grips the thread 16. This grip allows a single needlethreading which be may be aided by passing the thread through the loopmore than once.

The needle may thus be easily threaded and maintains a positive grip onthe sewing thread, and the resilient loop collapses and passes throughthe fabric being sewn following passage of the needle through the fabricwithout substantial distortion of the fabric beyond that imposed by theneedle and thereafter expands to reassume its unstressed configurationfollowing its passage through the fabric. The loop has sufficientrigidity such that it remains in the single common plane with the needleaxis as it collapses upon passage through the fabric and as it expandsto its unstressed configuration following such passage.

In the embodiment illustrated in FIGS. 4 and 5, the needle isconventional and includes a pointed end 40 and a trailing end 42 formedwith a conventional eye 44 with a pair of concave depressions 46 definedon opposite sides of the eye. The free ends 48 of a filament loop,generally indicated at 50, are swaged within these depressions. The freeends 48 of the filament loop 50 may also be secured to the conventionalneedle by applying sufficient heat to the end portion of the needle body38 near the eye 44 in order to increase its malleability, inserting thefree ends 48 of the filament loop into or through the eye 44, and thencollapsing the needle body 38 surrounding the eye by using mechanicalpressure or otherwise securing the filament ends therebetween. The loop50 lies in a single plane and preferably has the same diamond-likeconfiguration as the loop 18 used with the embodiment of FIGS. 1-3.

Those skilled in the art will appreciate that attachment techniques suchas swaging or crimping or otherwise embedding the free ends 20 of thefilament loop into the needle 10 are most effective when performedduring the manufacture of the needle, before the needle body 10 has beenhardened. It should be noted that any of the above-described embodimentscan be utilized to produce a finished product using a relativelymalleable needle body. However, when a filament loop 18 is being securedto a conventional sewing needle or a needle body that has alreadyundergone some hardening, the portion of the needle body to which theends of the filament loop are being attached should be exposed tosufficient heat to increase the malleability of the needle body beforeany crimping or swaging operation. As an alternative, adhesion means,such as a dry adhesive, welding or soldering may be utilized to affixthe filament ends 20 to an already hardened needle body.

The invention embodiment illustrated in FIG. 6 includes aneasy-threading needle 110 comprising a thin elongate needle body 112with a point 113 at one end and a thread-receiving section formed as aclosed loop 114 extending from the opposite end. Needle body 112 andloop 114 are formed from a single piece of material, such as plastic orspring steel. When forming the needle body 112 and loop 114 from asingle piece of plastic, conventional injection and/or compressionmolding techniques may be employed. The needle 110 may then be coated,such as by flashing with chrome or other metallic coating, to achievethe desired appearance.

Constructing the needle body and loop as a single unitary member, asshown in FIG. 6, provides an easy threading needle with a securelyaffixed loop without many of the manufacturing problems and costsassociated with similar prior art devices.

In the embodiment of the invention seen in FIGS. 7 and 8, a resilientmetallic diamond-shaped open filament loop or clip 62 is provided for aquick attachment to conventional sewing needles. In its normal relaxedcondition, the open ends 68 abut each other forming an acute angle atone end of the diamond-shaped loop 62. The clip may be attached to aconventional needle 64 by inserting the abutting ends 68 into the eye 66of the needle 64 and adhesively or otherwise securing the abutting ends68 to each other. The clip 62 may then be adhesively secured within theeye 66 of the needle 64, preferably along the inner end face 70 of theeye 66. The clip may also be adhesively secured to the depressions 72formed on opposite sides of the eye to obtain a more secure attachmentto the needle. It should be noted that the clip 62 can be formed as anopen loop with the ends nearest the acute angle at the trailing end 67of the loop 62 initially unattached. After insertion of the loop 62through the eye of a conventional needle 64, the trailing ends may thenbe secured to form the acute angle by butt welding or spot welding.

In any of the disclosed embodiments, the loop or, in the unitaryembodiment of FIG. 6, the entire needle assembly, may be formed from amaterial which glows in response to receipt of light energy so as toassist the user in clearly visually distinguishing the outline of theloop to facilitate passage of the thread through the loop. For example,the loop may be formed of a material incorporating a fluorescent dye.Specifically, the loop may be formed of a DAY-GLO™ material of the typedisclosed in U.S. Pat. No. 3,915,884.

Although the present invention has been described in connection with itsuse as a conventional hand sewing needle, the easy threading features ofthe present invention are equally advantageous in other sewingapplications, such as with surgical needles or darning needles. Thediamond shape of the filament provides for a quick and substantialflattening of the opposing sides of the loop under relatively lowtension to ensure that the hole formed by the needle is not enlarged bythe filament.

I claim:
 1. A sewing needle assembly comprising:an elongated rigidneedle having a pint at one end and defining a central axis; and afilament formed into a substantially diamond-shaped loop, having a pairof obtuse angles at opposite sides of the loop and acute angles atopposite ends of the loop, and an attachment portion at one end of theloop; said attachment portion of said filament being fixedly, immovably,and permanently secured to the other end of said needle with said looppositioned in trailing fashion behind said needle with said central axispassing through said acute angles of said loop so as to rigidly maintainsaid loop in trailing fashion to said needle in a single common planewith the lengthwise axis of said needle; said loop being resilient andoperative to collapse upon contact with the fabric being sewn followingpassage of said needle through the fabric and being further operative toexpand to reassume its unstressed expanded configuration following itspassage through the fabric, said loop irrespective of its collapsed orexpanded configuration maintaining a disposition wherein said centralaxis passes through said acute angles so as to facilitate threading ofthe loop with the loop in its expanded condition and so as to allow theloop to pass through the fabric in its collapsed configuration withoutsubstantial distortion of the fabric beyond that imposed by the needle;said loop being formed of a material which glows in response to receiptof light energy so as to clearly visually define the outline of theloop.